Here's a video of it in action:
As you can see, this allows you to switch between applications without having to wait on the "Resuming..." message. Of course, there's some side effects, but I assume everyone on here knows the drill. Here's the key:
Set it to 0 to disable dehydration. (Defaults to 3)
You don't even have to restart, just load up an application and lock the device to see the results. Cool, huh?
Now for the side effects:
First off, obviously, this probably won't help your battery much. But it actually might not be that bad, because the applications are still frozen in the background, just not dehydrated (evident with Fruit Ninja where the game pauses AFTER being returned to).
Second side effect involves the camera. With this enabled, sometimes the camera will let you take one picture, and then lock up entirely. This one is tricky, because it happened at first for a while, and then went back to being completely normal (can take pictures, view pictures, etc). Experiment a little with it, and tell me what happens.
The third also only appears sometimes (the same sometimes as when the camera started working again, hint hint), and is not that big of a deal. Basically, sometimes your icons won't load, for whatever reason. Again, this only happens sometimes, and doesn't really effect your device usage.
Side effects aside, this works without any hassle and is completely reversible. Just keep in mind that it is a hack, and you know the deal with those. As usual, it's at your own risk.
Try it out and share what happens.
More info: http://windowsphonehacker.com/articl..._hack-03-19-11